Quinton Coples was expected to bring big things to the Jets' defense this season. But now the team must figure out how to replace him for the time being.

The former first-round pick suffered a hairline fracture in his right ankle Saturday night against the Jaguars and is expected to miss three to four weeks, a source told Newsday after the game. Coples does not need surgery, the source said, but based on the recovery timetable, he'll miss Week 1 against the Bucs and, most likely, Week 2 in Foxborough four days later.

The Jets announced, "Quinton Coples suffered an injured right ankle Saturday night against Jacksonville and will undergo a medical procedure on Tuesday. He will miss the remainder of the preseason and is out indefinitely.''

Coples had a team-high 51/2 sacks in 2012, and Rex Ryan & Co. decided to add more to his plate this season, giving him outside linebacker duties. This setback couldn't have come at a worse time for Coples, who has struggled at times on the edge.

With the second-year defensive lineman sidelined, look for Antwan Barnes (who replaced Coples on Saturday night) to see more action. Outside linebackers Ricky Sapp and Garrett McIntyre also could get more snaps. It remains to be seen, however, how the Jets will replace Coples' athleticism inside in certain defensive packages.

Probe eyes ex-Jets doc

Former Jets team doctor Elliot Pellman -- a Long Island-based rheumatologist -- is at the center of NFL concussion litigation, according to an ESPN "Outside the Lines" report. Pellman's name reportedly appears 26 times in a lawsuit that claims the NFL "concealed" a link between football and brain damage. The article says that while Pellman was the Jets' team doctor -- and in charge of the NFL's mild traumatic brain injury committee, which helped to shape the league's concussion policies -- he "often" allowed athletes with concussions to return to games.

Pellman, who still is employed by the league, reportedly served as former commissioner Paul Tagliabue's personal physician for nearly a decade while he led the MTBI committee.

Former Jets center Kevin Mawae told "Outside the Lines'' that it was "pretty common" for players to go back into games after suffering a head injury during Pellman's tenure with the Jets "unless the guy was just out and carted off the field or something like that." Mawae, a Jet from 1998-2005, said Pellman would administer a simple test -- the ability to recite a sentence -- to make sure players were fit to return after a blow to the head. Said Mawae, "He would leave you and come back before the next series and you'd go, 'Red Brick Broadway. I'm ready to go.' "

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